Inking mechanism for duplicating machines



April 4, 1944. M. P. NEAL 2,345,681

INKING MECHANISM FOR DUPLICATING MACHINES Original Filed April '7, 19393 Sheets-Sheet l Harri P" 1944- M. P. NEAL INKING' MECHANISM FORDUPLICATING MACHINES Original Filed April 7, 1939 3 Sheets-Sheet 2 07W?Sv April 1944- M. P. NEAL 2,345,681

INK ING MECHANISM FOR DUPLICATING MACHINES Original Filed April 7, 19393 Sheets-Sheet 3 Patented Apr. 4,1944

2,345,881 I mama MECHANISM roa nnmcs'rme MACHINES I Morris 2. ideal,Quincy, m, assignor to mm. m-

eriirrporated, Chicago, 111., a corporation of West OriginalapplicationApril 1, 193-9, Serial No. 268,518. Divided and this application mm 25,1941, Serial No. 418.544

Claims.

The invention relates to duplicating apparatus and particularly to animproved form of blackline duplicating apparatus employing a drum havinga master sheet thereon in the form of a. thin sheet of aluminum or thelike upon which a suitable ink repellent may be spread for controllingthe eflective application of ink to the sheet. My present improvementsare not however to be restricted to use in connection with this type ofmachine, so far as they are applicable to other types of machines.

It is one of the objects of this invention to provide an improved formand arrangement of operating and control parts in a machine of this typewhereby the operator is enabled easily and quickly to stop the movementof the copy sheets through themachine and at the same time to stop orcurtail the operation 0% certain other parts. To this end it is theobject of the present invention to provide an improved arrangement ofinking means which can be readily controlled as desired and which atthe. same time shall be highly eifective for cutting and tempering theink thoroughly so as to be applied evenly on the face of the mastersheet on the drum.

It is another object of the invention to provide improved control meansby which the desired sequence may be attained in the preparation of theparts for operation of the machine and the desired sequence in thewithdrawal of'the different mechanisms from operative condition so as toenable the operator to best advantage to proto engage the face of theroller. A set screw is provided bearing against the outside face of theI mounted so as to be movable toward and from the vide for an intervalof rest for at least a portion of the operative mechanisms withoutpermitting the mechanisms to get out of operative condition, thusenabling the operator to renew operation without a prolongedreconditioning procedure;

For attaining these ends I have provided a drum comprising two separateportions of different size radially, upon the smaller of which drumportions the ink is primarily spread and equalized by cutting rollers orthe like, after which the ink is taken off by an ink transfer roller andreapplied on the form carried by the larger drum portion, from which inturn the ink is transferred to the copy sheets under the influence ofthe pressure applied by the impression roller. For permitting thisoperation, the impression roller is pressed firmly against the drumportion of greater diameter but is held out of engagement with the drumportion of smaller diameter.

A novel form of ink supporting and feeding vmeans is provided,comprising a fountain roller face of the fountain roller, and a thirdroller is mounted so as to be movable back and forth between the secondroller and the drum section of smaller diameter. The parts are arrangedso that the movement of the third roller into engagement with the secondroller causes the second roller to move out of engagement with thefountain roller. Means is also provided for giving the fountain roller aslight rotary movement upon each movement of the second roller away fromthe fountain roller, this being accomplished preferably by the use of alatch pawl movable with the second roller and engaging a ratchetrotatable with the fountain roller. Means is also provided for givingthe third roller reciprocatory movement longitudinally as itengagesfirst the second roller and then the drum, this means comprisingpreferably a cam member carried by said third roller and having acompound groove in its face engaged by a swiveled follower mounted onthe framework of the machine.

It is another object of the invention to improve mechanisms of this typein sundry details'hereinafter pointed out. The preferred means by whichthe several objects have been attained are illustrated in theaccompanying drawings in which- Fig. l is a vertical sectional viewthrough a duplicating machine embodying my invention but with some ofthe parts removed and other parts broken away, the section being takenat a point adjacent to the end of the drum;

Fig. 2 is a vertical sectional view of a fragmentaryportion of theapparatus showing the ar-- rangement of the means for giving one of theink-' in rollers a longitudinal reciprocatory movement;

Fig. 3 is a top face view of the operating cam of the apparatus showninFig. 2, being shown substantially as seen at the line 3-3 of Fig. 2;

Fi 4 lab. vertical sectional view taken at an intermediate point throughthe inking mechanism and at. a point adJacent to the end of the drum soas to show the operating-cam at another por-.

tion of the view;

Fig. is a view similar to a portion of Fig.4 but with certain of theparts in changed position, and showing a fragmentary portion of the drumin its operative relationship to the inking mechanism;

Fig. 6 is a fragmentary detailed view showing diagrammatically a portionof the driving means for the sheet forwarding roller; and

Fig. 'l is a vertical sectional view similar to Fig. 1 but taken at aslightly different point so drawings in which corresponding parts areindi- -cated by the same reference characters. lit indicates theframework of the duplicating machine supporting a heavy shaft H which inturn supports a drum comprising two sections I2 and I3 which are mountedin fixed position with respect to each other with openings between thecircumferential wall portions of the sections at opposite sides of thedrum. The drum section I2 is of slightly greater diametrical size thanthat of the section l3, being provided with a master sheet l4 wrappedthereabout and secured thereto by any suitable means. The drum sectionI3 is provided with an ink pad l5 wrapped about its curved face andsecured in position by any suitable holding means. The drum is normallydriven in counterclockwise direction in Fig. 1 by means of a large gearI6 which is fixedly connected with the drum sections l2 and I3.

In Fig. 1 a fragmentary portion of a table or tray I I is shown,supporting a pile of copy sheets l8 stacked against a verticallydisposed plate l9 at the forward edge of the pile of sheets. A shortdistance in advance of the table I! (toward the right in Fig. 1) aplaten or impression ro1ler20 is rotatably mounted in position so as topress on the master sheet l4 carried by the larger drum section as thedrum rotates but so as to be held out of pressure relationship withrespect to the smaller drum section I3. In the construction 11-lustrated the impression roller 20 is rotatably supported by pivotallymounted arms 2| which are pressed upwardly by spring supported plungers22. Means is provided for moving the impression roller 20 downwardly outof position for engagement with the drum section l2 when desired, suchmeans being provided for use in part in connection with the inkingmechanism and being hereinafter described.

Above the table or tray I! in position to engage the top sheet of thepile of copy sheets I8 I have mounted a forwarding roller 23 supportedby a shaft 24 and driven in counterclockwise direction in Fig. 1 by apinion 25 meshing with a toothed sector 26 which is'swung back and forthby any approved arrangement of actuating means during the rotation ofthe drum. A one-way clutch 21 of any approved type is preferablyinterposed between the pinion 25 and the forwarding roller 23 so as topermit the roller to stand stationary upon the stroke of the sector 23in one direction.

In the arrangement shown, means is provided for applying an inkrepellent upon the face of 1 the master sheet in advance of theapplication into and out of position to take a supply of the repellentfrom a receptacle 3!], the roller 29 being rotatably mounted on a bellcrank lever 3| actuated as the drum rotates by a roller 32 engaging cams33 and 34 carried by the drum. Inasmuch as this mechanism forms in andof itself no part of the present invention, it is believed to beunnecessary to describe the same-further herein.

For stopping the forward movement of the copy sheets as they are fed tothe drum, a margin bar arrangement is provided, comprising arms 35adapted to swing circumferentially of the drum in the space between thetwo sections l2 and I3. The arms 35 normally stand in position adjacentto the rear edge portion of the drum section l3, but as the drumrevolves in counterclockwise direction in Fig. l rollers 35 carried bysaid arms engage latch devices 31 by which the margin bar device is heldstationary for a, short period, during which time it serves effectivelyas stop means for limiting the forward feed of the copy sheets by therollers 23. As soon as the section l2 of the drum is brought intoengagement with the arms 35, such arms are pushed forwardly out ofengagement with the latch devices 31, whereupon the arms are carriedagain to their noririal position adjacent to the drum section l3. Thismeans also forms no part of the present invention.

The means for moving the impression roller 20 downwardly out ofoperative position manually comprises a lever 38 fixedly mounted on atransversely extending shaft 39 positioned a short distance in front ofsaid impression roller 20. This shaft is provided with pins 40 extendingtherethrough, the rear end portions of such pins being in engagementwith openings in brackets 4| depending from a crossbar 42 which connectsthe front ends of the arms 2|. The arrangement is such that when thelever 38 is given a downward stroke'in counterclockwise direction inFig. 7 the pins 40 cause the brackets 4| and the arms 2| to movedownwardly for carrying the impression roller 20 out of position forengagement with the drum.

The improved means for applying ink upon the master sheet [4 comprises aheavy plate 43 preferably in the form of an angle extending across themachine in position to be removably supported by a frame bar 44. At itsopposite ends the plate 43 is provided with upstanding portions 45having a fountain roller 46 journalled between them. A heavy scraperplate 4'! is also pivotally mounted between the end portions 45 so as toengage the bottom face portion of the roller, a set screw 43 beingprovided for pressing the plate 41 adjustably against the roller 46. Inthe arrangement shown, the set screw 48 is arranged in acute anglerelation to the plate 41, being secured by screw threads in a lug 49carried by the plate 43. The arrangement is such that when a supply ofink is provided between the plate 41 and the roller 43, a film of ink ofcontrolled thickness is carried around by the roller 46 when it isrotated in counterclockwise direction in Figs. 4 and 5.

For taking ink from the fountain roller 45 I have provided a vibratingdistributor roller II which is Journaled between two bowed arms llpivotally mountedon the end plates or standards 45, respectively, thearrangement being such that when the arms are swung to the limitof'their motion in clockwise direction in Fig. 4 the roller 50 isbrought into operative engagement with said fountain roller 45. The armsII are connected by coiled springs 52 with the plate 43 for .pawl 53which is pivotally mounted on one of the arms 5| (see Fig. 4) adapted byengagement with a ratchet wheel 54 carried by the roller 4| to give saidroller a limited rotary movement in counterclockwise direction in saidfigure when the arms ii are swung in counterclockwise direction formoving the roller 50 out of engagement with said roller 48.

The means provided for swinging the arms 5i upwardly in counterclockwisedirection in Fig. 4 comprises a roller 55 extending across the machinein front of the roller 50, such roller 55 being iournaled between arms56 pivotally mounted on a crossbar 51 extending between portions of theframework III at opposite sides of the machine. The arms 55 are normallyurged to the limit of their swinging movement toward the drum by coiledsprings 58 interposed between said arms and lugs 59 extending inwardlyfrom the framework, and said arms are moved outwardly away from the drum(toward the left in Fig. 4) by rollers 80 carried by said arms inposition to engage cams 6i and 62, respectively, mounted on oppositeends of the drum. The roller 55 is supported between the arms 56 by ashaft imlong which the roller is slidable longitudin The arrangement asabove described is such that when the rollers 60 are in engagement withthe low portions of the cams SI and 52 said roller 55 stands in spacedrelation to the roller 50,

" but that when the rollers 50 are engaged by the high portions of saidcams the arms 58 are swung toward the left in Fig. 4, serving. to carrythe roller 55 into engagement with the roller 50, and serving also tomove said roller 50 upwardly out of engagement with the fountain roller45. The arrangement of the cams GI and 62 angularly with respect to thedrum is such that the roller. 55 in its inwardly swung position engagesthe ink pad or blanket I5 carried by the drum section It of smallerdiameter, and that said roller in its outwardly swung position stands inspaced relation to the master sheet l4 carried by the drum section I! ofgreater diameter.

In the arrangement shown, the roller 55 is driven continuously by a gear63 carried by the roller (see Fig. 4), such gear 63 meshing with anidler gear 64 which in turn meshes with a second idler gear 65 mountedon a lug 66, such gear 65 meshing with the large gear it carried by thedrum. The arrangement is such that the 1 the gear 83 is positionedsubstantially on the I line of centers between' the gear 64 and thecrossbar 51 about which the arms 58 swing. This arrangement enables thegear BI to be given a slight movement toward and away from the drumwhile in mesh with the gear 04 without interfering with the smoothmeshing of the parts.

Means is also provided for giving the roller 85 longitudinal movementswith respect to the blanket or pad I! and with respect to the roller IIfor assisting in the cutting of the ink and in the distribution of theink along the cooperating rollers. This means comprises a cam member I!carried by the roller 55 so as to be slidable therewith along the shaft55a, such cam member having a compound cam groove 58 into which aswiveled follower 60 extends, as shown in Fig. 2, such follower 88 beingrotatably mounted on a bracket 10 which in turn is fixedly mounted onone of the arms 58, as is shown in Fig. 1. The arrangement is such thatupon one revolution ofsthe cam the cam and the roller 55 are movedlongitudinally in one direction and that upon the next revolution thecam and roller are moved in the reverse direction, such reciprocation ofthe roller continuing without break during the rotation of said roller.

By the use of the mechanism as just described, ink is taken from thefountain comprising the roller 45 and the adlustable plate 41 and isdistributed by the co-operation of the rollers 46, 50 and 55. The amountof the ink is controlled by the pressure of the plate 41 on the roller46, the rollerv 48 being given only a comparatively small part of acomplete revolution upon each actuation of the roller by the pawl 53.

In the arrangement illustrated, the roller 55 is given a completereciprocation back and forth for each two revolutions of the roller andin view of the fact that said roller 55 is given a considerable numberof revolutions during each revolution of the drum, it will beappreciated that the ink as applied to the ink pad I 5 on the drumsection I3 is quite thoroughly worked and cut and is applied verysmoothly and evenly upon the pad.

For taking the ink from the pad l5 to which it has been applied by therotating and longitudinally moving roller 55, and applying such ink evenmore uniformly to the master sheet H on the drum portion I 2, I haveprovided a form roller H which is journaled between two arms 12, one ofsaid arms being pivotally mounted on the lug 55, and the other of whichat the opposite side of the machine is pivotally mounted upon 8. lug 13extending inwardly from the framework Ill as is clearly shown in Fig. 1.These arms 12 are connected by coiled springs 14 with the shaft or bar51, such springs serving normally to'urge the form roller 1! toward thedrum. As is clearly shown in Fig. 1, each' of the arms 12 is providedwith a set screw 15 adJustably mounted in position to engage one of thelugs 59 for limiting the movement of the form roller toward the right insaid Fig. 1. The arrangement of the parts is such that the form rolleris pressed by the springs 14 yieldingly against the pad or blanket l5 onthe drum section l3 so as to take ink therefrom and then in turn ispressed against the master sheet H on the drum section II so as to applythe ink to said master sheet. The set 12 in position to engage suitablecams carried by the drum for carryingthe form roller smoothly sections[2 and I3, which are in spaced relation circumferentially with respectto each other and are of different diametrical size, as hereinbefore setforth. The roller H5 at one side of the machine engages the cams 33 and34 for such bridging action, while the roller 16 at the opposite side ofthe machine engages similar cams not shown.

Means is provided for moving the form roller H to the left in Fig. 7away from the drum when the lever 38 is given an operative strokedownwardly. This means comprises-a link 11 pivotally connected at itslower end with said lever 38 and pivotally connected at its upper endwith a downwardly bowed arm'lfl which is non-rotatably connected with arock shaft I9. The shaft 19 is provided atopposite sides of the machinewith short arms or lugs 80 which are adapted by engagement with lugs orrollers 8| carried by the arms 12 to sv lg said arms 12 towards the leftin Fig. 7 for carrying the form roller H out of position for engagingthe drum when said shaft 19 is given a rotary movement in clockwisedirection in said Fig. 7 by a downward stroke of the lever 38. In Fig. 7the arms or lugs 80 are shown out of engagement with the lugs or rollersHi, this position of the parts corresponding 'with the normal raisedposition of the lever 38.

When the lever 38 is moved downwardly, the arms or lugs 80 displace therollers BI and the arms 12 against the action of the springs 14 forcarrying the form roller H away from the drum.

By the use of the improved arrangement as above. described, an operatoris enabled to throw the ink transfer roller H out of position forengagement with the drum and to move the impression roller 20 downwardlyout of position for engagement with the larger drum section l2, thisbeing accomplished by a downward movement of the lever 38.

Under such circumstances, the drum is adapted to continue rotation withthe ink repellent being continuously applied upon the master sheet l4and with the ink also being applied by the roller 55 upon the face ofthe master sheet. Such movement of the lever 38 downwardly is adaptedalso to throw out of operation the means by which the copy sheets arefed forwardly to the drum, although such operation is not describedherein. By the use of this arrangement an operator is enabled to have apartial operation of the machine such as to enable him to clear up anypossible difllculties which may have arisen in connection with theprogress of the copy sheets one at a time through the machine. Duringthis corrective action on the part of the operator the film of ink onthe master sheet is kept tempered ready for immediate copy operation ofthe machine upon an upward stroke of the lever 33 to the normaloperating position.

By the provision of the means as shown and described for controlling themovement of the rollers and I have provided a very eifectiveconstruction which is easy to manufacture and easy to regulate andcontrol so as to obtain highly effective results.

While the form and arrangement of parts as shown in the drawings and asabove described are preferred the invention is not to be limited to sucharrangement, except so far as the claims may be so limited, it beingunderstood that changes might well be made in the construction 1withoutdeparting from the spirit of the invenion.

I claim:

1. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different effective diameter,means for mounting a master sheet on the face of the drum portion ofgreater diameter, means for rotating said drum, an ink foun; tain, meanscomprising a plurality of rollers for taking ink from said fountain andapplying such ink in comparatively well out condition on the drumportion of smaller diameter, means for holding said ink applying meansout of operative engagement with the drum portion of greater diameter, aroller rotatably mounted on a movable axis so as to be movable inwardlyand outwardly with respect to the drum, and means actuated in timedrelation to the rotation of the drum for moving said last-named rollersuccessively into engagement with both of said drum portions for takingink from the portion of smaller diameter and applying it to the mastersheet on the drum portion of greater diameter.

2. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different effective diameter,means for mounting a master sheet on the face of the drum portion ofgreater diameter, means for rotating said drum, an ink fountain, meanscomprising a plurality of rollers for .t-aking ink from said fountainand applying such ink in comparatively well out condition on the drumportion of smaller diameter, means comprising a cam rotating with saiddrum adapted upon a portion of each revolution of the drum to hold saidink applying rollers out of engagement with said drum portion of greaterdiameter and adapted upon another portion of each revolution of the drumto permit the rollers to move inwardly into effective engagement withthe drum portion of smaller diameter, a roller rotatably mounted on amovable axis adjacent to said drum, yielding means for pressing saidlastnamed roller toward said drum, and means comprising a cam rotatingwith the drum adapted at portions of successive revolutions of the drumto move said last-named roller outwardly against the action of saidyielding means into position to engage both portions of the drum in turnso as to take ink from the portion of smaller diameter and to apply suchink to the master sheet on the portion of greater diameter.

3. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different effective diameter,means for mounting a master sheet on the face of the drum portion ofgreater diameter, means for rotating said drum, an ink fountain, meanscomprising a plurality of rollers for taking ink from said fountain andapplying such ink in comparatively well out condition on the drumportion of smaller diameter: means comprising a cam rotating with saiddrum adapted upon a portion of each revolution of the drum to hold saidink applying rollers out of engagement with said drum portion of greaterdiameter and adapted upon another portion of each revolution of the drumto permit the rollers to move inwardly into effective engagement withthe drum portion of smaller diameter, a roller rotatably mounted on amovable axis adjacent to said drum, yielding means for pressing saidlastnamed roller toward said drum into position to engage both portionsin turn so as to take ink from the portion of smaller diameter and toapasaaosr ply it to the master sheet on the portion of greater diameter,and adjustable means for limiting the inward movement of said last-namedroller for controlling the pressure of said roller against the drumportion of smaller diameter.

4. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of diiferent diameter, means forattaching a master sheet on said drum portion of greater diameter, meansfor rotating said drum, an ink fountain comprising a rotatably mountedfountain roller adapted upon rotary movement to withdraw a film of inkof controlled thickness from the fountain, a second roller movabletoward and from said fountain roller, a third roller movable betweensaid second roller and said drum so as to engage them alternately, meansadapted upon each revolution of the drum to move said third roller awayfrom the drum into engagement with said second roller for carrying saidsecond roller out of engagement with said fountain roller, and a fourthroller mounted in position to engage both of said portions of the drumfor taking the ink from said portion of smaller diameter and applying itupon the master sheet carried by the drum portion of greater diameter.

5. In a duplicating machine, the combination of adrum rotatably mountedin position and comprising two portions of different diameter, means forattaching a master sheet on said drum portion of greater diameter, meansfor rotating said drum, an ink fountain comprising a rotatably mountedfountain roller adapted upon rotary movement to withdraw a film of inkof controlled thickness from the fountain, a second roller movabletoward and from said fountain roller, a third roller movable betweensaid second roller and said drum so as to engage them alternately, meansadapted upon each revolution of the drum to move said third roller intoengagement with said second roller for carrying said second roller outof engagement with said fountain roller, means actuated by themovement-of said second roller with respect to said fountain roller forgiving said fountain roller a slight rotary movement, and a fourthroller mounted in position to engage both of said portions of the drumfor taking the ink from said portion of smaller diameter and applying itupon the master sheet carried by the drum portion of greater diameter.

6. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different diameter, means forattaching a master sheet on said drum portion of greater diameter, meansfor rotating said drum, an ink fountain comprising a rotatably mountedfountain roller adapted upon rotary movement to withdraw a fllm of inkof controlled thickness from the fountain, a second roller movabletoward and from said fountain roller, a third roller movable betweensaid second roller and said drum so as to engage them alternately, meansadapted upon each revolution of the drum to move said third roller intoengagement with said second roller for carrying said second roller outof engagement with said fountain roller, means compflsing a latch pawlmovable with said second roller adapted by engagement with a ratchetcarried by said fountain roller to give said fountain roller a slightrotary movement upon each movement of said second roller away from thefountain roller, and a fourth roller mounted in position to engage bothof said portions of the drum for taking the ink from said portion ofsmaller diameter and applying it upon the master sheet carried by thedrum-portion of greater diameter.

7. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different effective di-'ameter, means for rotating said drum, means for mounting a master sheeton the face of the drum portion of greater diameter, means for applyingink to the drum portion of smaller diameter, means for holding said inkapplying means out of engagement with the drum portion of greaterdiameter, arms pivotally mounted adjacent to said drum, a rollerrotatably mounted on the free end portions of said arms, yielding meansnormally pressing said roller into position to engage said drum fortaking ink from the portion of smaller diameter and applying it upon themaster sheet carried by the portion of greater diameter, adjustablemeans for limiting the movement of said arms toward said drum forcontrolling the pressure of said roller on. the, drum portion of smallerdiameter, and manually operable means for moving said roller out of theposition in which it engages said drum.

8. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different effective diameter,means for rotating said drum, means for mounting a master sheet on theface of the drum portion of greater diameter, means for applying ink tothe drum portion of smaller diameter, means for holding said inkapplying means out of engagement with the drum portion of greaterdiameter, arms pivotally mounted adjacent to said drum, a rollerrotatably mounted on the free end portions of said arms, yielding meansnormally pressing said roller into position to engage said drum fortaking ink from the portion of smaller diameter and applying it upon themaster sheet carried by the portion of greater diameter, a shaftrotatably mounted adjacent to said arms, lugs on said shaft adapted byengagement with said arms to move them for carrying said roller out ofengagement with said drum, a lever pivotally mounted adjacent to saiddrum, and operative connections between said lever and said shaftadapted upon a stroke of the lever to rotate the shaft in the directionfor moving said roller away from the drum.

9. In a duplicating machine, the combination of a drum rotatably mountedin position and comprising two portions of different diameter, means forrotating said drum, means for attaching a master sheet on the drumportion of greater diameter, an impression roller rotatably mountedadjacent to said drum in position to engage said drum portion of greaterdiameter but held out of engagement with said drum portion of smallerdiameter, ,means for applying ink to said drum portion of smallerdiameter but held out of operative engagement with said master sheet onthe drum portion of greater diameter, ink transfer means for taking inkfrom the drum portion of smaller diameter and applying it to the drumportion of greater diameter, and means comprising a lever adapted by anoperative stroke in one direction to move said impression rolleroutwardly out of position for engaging said drum and for throwing saidink transfer means out of operation while the drum continues to rotateand said first-named ink applying means continues to operate.

10. In a duplicating machine, the combination of a drum rotatablymounted in position and comprising two portions of diflerent diameter,means for rotating said drum, means for attaching a master sheet on thedrum portion of greater diameter, an impression roller rotatably mountedadjacent to said drum in position to engage said drum portion of greaterdiameter but held out of engagement with said drum portion of smallerdiameter, means for feeding copy sheets between said drumand saidimpression roller, means for applying an ink repellent to said mastersheet, means for applying ink to said drum portion of smaller diameterbut held out of operative engagement with said master sheet, otherineans for taking the ink from said drum portion of smaller diameter andapplying it to the drum MORRIS P. NEAL.

